deceit, deception, fraud
这3个名词均含有欺骗之意。
deceit : 指歪曲实情，惯于说谎或蓄意欺骗。
The boys deceit made his mother very unhappy.
deception : 语气较弱，一般用词，侧重于具体的骗人行为。但有时并无欺骗行为，只是玩弄把戏，故弄玄虚而已。
Nobody saw through Marys deceptions.
fraud : 一般用于犯罪行为的欺骗，通常指政治或经济活动中的舞弊行为。
He said he was an insurance salesman, but later she discovered he was a fraud.